1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
|
//---------------------------------------------------------------------------//
// Copyright (c) 2013 Kyle Lutz <kyle.r.lutz@gmail.com>
//
// Distributed under the Boost Software License, Version 1.0
// See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt
//
// See http://boostorg.github.com/compute for more information.
//---------------------------------------------------------------------------//
#ifndef BOOST_COMPUTE_ITERATOR_PERMUTATION_ITERATOR_HPP
#define BOOST_COMPUTE_ITERATOR_PERMUTATION_ITERATOR_HPP
#include <string>
#include <cstddef>
#include <iterator>
#include <boost/config.hpp>
#include <boost/iterator/iterator_adaptor.hpp>
#include <boost/compute/functional.hpp>
#include <boost/compute/detail/meta_kernel.hpp>
#include <boost/compute/detail/is_buffer_iterator.hpp>
#include <boost/compute/detail/read_write_single_value.hpp>
#include <boost/compute/iterator/detail/get_base_iterator_buffer.hpp>
#include <boost/compute/type_traits/is_device_iterator.hpp>
namespace boost {
namespace compute {
// forward declaration for transform_iterator
template<class ElementIterator, class IndexIterator>
class permutation_iterator;
namespace detail {
// helper class which defines the iterator_adaptor super-class
// type for permutation_iterator
template<class ElementIterator, class IndexIterator>
class permutation_iterator_base
{
public:
typedef ::boost::iterator_adaptor<
::boost::compute::permutation_iterator<ElementIterator, IndexIterator>,
ElementIterator
> type;
};
template<class ElementIterator, class IndexIterator, class IndexExpr>
struct permutation_iterator_access_expr
{
typedef typename std::iterator_traits<ElementIterator>::value_type result_type;
permutation_iterator_access_expr(const ElementIterator &e,
const IndexIterator &i,
const IndexExpr &expr)
: m_element_iter(e),
m_index_iter(i),
m_expr(expr)
{
}
ElementIterator m_element_iter;
IndexIterator m_index_iter;
IndexExpr m_expr;
};
template<class ElementIterator, class IndexIterator, class IndexExpr>
inline meta_kernel& operator<<(meta_kernel &kernel,
const permutation_iterator_access_expr<ElementIterator,
IndexIterator,
IndexExpr> &expr)
{
return kernel << expr.m_element_iter[expr.m_index_iter[expr.m_expr]];
}
} // end detail namespace
/// \class permutation_iterator
/// \brief The permutation_iterator class provides a permuation iterator
///
/// A permutation iterator iterates over a value range and an index range. When
/// dereferenced, it returns the value from the value range using the current
/// index from the index range.
///
/// For example, to reverse a range using the copy() algorithm and a permutation
/// sequence:
///
/// \snippet test/test_permutation_iterator.cpp reverse_range
///
/// \see make_permutation_iterator()
template<class ElementIterator, class IndexIterator>
class permutation_iterator
: public detail::permutation_iterator_base<ElementIterator,
IndexIterator>::type
{
public:
typedef typename
detail::permutation_iterator_base<ElementIterator,
IndexIterator>::type super_type;
typedef typename super_type::value_type value_type;
typedef typename super_type::reference reference;
typedef typename super_type::base_type base_type;
typedef typename super_type::difference_type difference_type;
typedef IndexIterator index_iterator;
permutation_iterator(ElementIterator e, IndexIterator i)
: super_type(e),
m_map(i)
{
}
permutation_iterator(const permutation_iterator<ElementIterator,
IndexIterator> &other)
: super_type(other),
m_map(other.m_map)
{
}
permutation_iterator<ElementIterator, IndexIterator>&
operator=(const permutation_iterator<ElementIterator,
IndexIterator> &other)
{
if(this != &other){
super_type::operator=(other);
m_map = other.m_map;
}
return *this;
}
~permutation_iterator()
{
}
size_t get_index() const
{
return super_type::base().get_index();
}
const buffer& get_buffer() const
{
return detail::get_base_iterator_buffer(*this);
}
template<class IndexExpr>
detail::permutation_iterator_access_expr<ElementIterator,
IndexIterator,
IndexExpr>
operator[](const IndexExpr &expr) const
{
return detail::permutation_iterator_access_expr<ElementIterator,
IndexIterator,
IndexExpr>(super_type::base(),
m_map,
expr);
}
private:
friend class ::boost::iterator_core_access;
reference dereference() const
{
return reference();
}
private:
IndexIterator m_map;
};
/// Returns a permutation_iterator for \p e using indices from \p i.
///
/// \param e the element range iterator
/// \param i the index range iterator
///
/// \return a \c permutation_iterator for \p e using \p i
template<class ElementIterator, class IndexIterator>
inline permutation_iterator<ElementIterator, IndexIterator>
make_permutation_iterator(ElementIterator e, IndexIterator i)
{
return permutation_iterator<ElementIterator, IndexIterator>(e, i);
}
/// \internal_ (is_device_iterator specialization for permutation_iterator)
template<class ElementIterator, class IndexIterator>
struct is_device_iterator<
permutation_iterator<ElementIterator, IndexIterator> > : boost::true_type {};
} // end compute namespace
} // end boost namespace
#endif // BOOST_COMPUTE_ITERATOR_PERMUTATION_ITERATOR_HPP
|
